I dunno if it's the same in the rest of the country, but people here are really suspicious, and will call the cops if they see things, just to check to make sure.
My friend had the police ask him more then once, that a person called them up to check the situ. But I guess if your known by them, by business name and name, then they wouldn't check me out?
I dunno, it was advice given to me by a fellow windowcleaner, also by a few customers.